<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>
<style>
  .circle-red{
    background-color: red;
    width: 100px;
    height: 100px;
    position: fixed;
    left: 200px;
    top: 200px;
    border-radius: 50%;
    /* transition: 0.1s ease-in-out; */
  }
</style>
<body>
  <div>

    <div class="circle-red"></div>
  </div>
  <script src="index.js"></script>
</body>
</html>